Hi, I’m hoping someone will be able to help me, i’ll explain what the
problem is but forgive me as the history of this is quite long.

I have a problem with the immobiliser on my Peugeot 306, when i turn
the ignition on, both the Red and Green light comes on on the keypad
and won’t accept my 4 digit code, had a mechanic look at it and he
said the ECU had locked out, so found a place that sorts out ECU’s and
they said make sure it not an earth fault before sending them the ECU,
so the mechanic checked and said no, there’s no earth fault!

So sent ECU to be done, came back, still the same problem, ECU place
said it wasn’t ECU, so decided theres nothing else i can do but to
take it to the Peugeot garage, they had a look, connected it to their
computer and said they couldn’t find what it was, can only be the ECU
locked out, so i sent the ECU back to the ECU repair place and they
said it wasn’t the ECU and to tell your garage its ’PIN 18 - Battery
supply fault’, so i did, they said they’ve completely checked
everything and cannot find the fault and they still believed it was
the ECU, which left me well in the s**t, a private mechanic, the
agents and an ECU repair place, all these so-called experts still
haven’t found what the problem is!!

Anyway, on verge of scrapping the car, i managed to get hold of a
second hand ECU, keypad and code to try, which show’s up with the
exact same problem which leads me to believe its not the ECU.

If there’s anyone out there that can offer me any advice or info on
what to do next i would be very grateful, i’m assuming it must be an
earthing problem but haven’t got a clue how to find it, cleaned up all
the earthing points i can find but still no joy!

I’m about to string myself up as the car has now been out of action
for over a year, so any help would be great!!